Boiler



Aug. 12, 1952 N. G. SANDSTROM 2,606,535

BOILER Filed March 14, 1946 5 Sheets-Sheet 1 1 v VZLZQMA IN V EN TOR.

Aug. 12, 1952 N. G. SANDSTROM 2,606,535

BOILER Filed March 14, 194 5 Sheets-Sheet 2 IN V EN TOR.

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Aug. 12, 1952 I N. G. SANDSTROM 2,605,535

BOILER Filed March 14, 1946 5 Sheets-Sheet s 44// K zmwnc INVENTOR.

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Aug. 12, 1952 N. G. SANDSTROM 2,606,535

I BOILER Filed March 14, 1946 5 Sheets-Sheet 4 INVENTOR. BY W may N. G. SANDSTROM BOILER 5 Sheets-Sheet 5 Filed March 14, 1946 A ID 2 w B J H w m w I FWMHHMT hull. Harm L 1 Q U m u H w v W u l A v q v 2 q u I d u W q 4 m u T u d U m L A u INVENTOR.

Patented Aug. 12, 1952 BOILER Nils-G. Sandstrom, :Erie, Pa., :assignor .to=Erie- Gity. .Iron Works, :Eri-e, ;Pa., a corporation nfI'enn- .sylvania.

Application-Marchll l,1946,iSeria1;N0.T654;413 V .l Thisinvention is intended to improve :the gas bafiling :in water tube boilers. .Heretoiore :all boilers of this type have customarily employed bafiles which caused an up and :down undulating flow of gases. Thepresent system eliminates up and down flow, resulting in less resistance through the heating surfaces and providing other advantages which become apparent from the accompanying drawings and description.

Figure 1 is a side view .of the boiler with near outside wall removed. a Figure 2 is a section on line 2--2 of Fig. 1. Figures 3, 4 and are sectional elevations of baffles taken on 3-3; 4-4; and 5-5 respectively of .Eig. l.

Figure 6 is a view similar to Fig. 1 of a boiler equipped with settling hoppers for use with'sdust bearing gases.

Figure 7 shows alternate arrangements 10f flue gas outlets from rear boiler pass.

Referring "to the drawings, there is shown 'a water tube boiler having at one end a combustion space I which may be fired in any suitable manner (not shown), with liquid, gaseous or solid fuels. Part of the heat of combustion is absorbed radiantly by furnace wall tubes 2 connected between headers 2a and an upper drum 2b. The remainder of the heat of combustion raises the temperature of combustion gases which rise and pass rearwardly over a bridgewall 3. The restriction to fiow caused by close spacing of convection tubes 4 connected between the upper drum 2b and a lower drum 4a forces the gases to completely occupy space 5 between the bridgewall and the convection tubes and enter the first pass of the convection zone over its entire width. The gases pass through the first convection zone 6, which is illustrated as five rows of tubes 4. On approaching the rear of the first pass, the gases are forced to the center of the pass by vertical battles I extending inward from each side of the boiler. At

the lower end of the bafiles 1 is a cross wall 1a 7 which provides a dust settling chamber below the lower ends of the tubes of the first convection pass. Upon passing horizontally through the opening between baflies fl and above the cross wall la, the gases enter the second convection pass 8. At theend of the pass 8 and at the center of the boiler is a vertical bafile 8 which causes the gas flow to divide equally, one-half flowing to the right and the other half moving to the left. Upon leaving pass 8 the gases enter settling chambers l0 and reversing their direction, enter convection pass H from each side. Bafiles l2 on each side of the boiler 3 .Claims. (015122-347) force the :gas streams back to =the center :and horizontally through the =opening between baffies .12. At the lower ends of the baffles 12 are plates llclosing-theendsmf the settling chambers .Hl. Gas-travel through .the last convection-section t3 .isagaimdivided from the center and the gases-travel upwardly. and outwardly to .the flue gas outlets t5. at each side of the boiler. Eromthis it will be seen that the gases of combustion travel horizontally from combustion space I to rear convection pass, being alternately drawn to the .center and.itheniorced to .the outsides. Inthis manner transfer is improved because all gas 1 flowfiswpe pendicular .to the vertical watertiibes.

Fig. '6 shows dust hoppers; 16 it l'ai'id is placed below settling chambersi, ifiland 1'4. fThe gases passing through these chambers slow down and reverse their direction of now. his this occurs. dust settles out into the hoppers tor ready removal. The tubes 2 linejthe outside wa'lls oi the settling chamber. 1

Fig. "7 shows a view of 'thelast pass"l3.' Since the bafile I2 is symmetrical with respect to the upper and lower drums 2b, 4a and extends the same distance in from each side wall, gas density entering the last pass is the same regardless of position between drums.

From this it is apparent that the flue gas outlets from the boiler may be either at the top (l5), rear (I5A) or bottom (I5B) without altering the boiler bafiling in the slightest way.

While the illustrations and description cover the bafliing applied to a vertical tube, longitudinal drum boiler, it will be understood that any water tube boiler can be so baflied. The same type boiler with an upper drum of equal length as the lower one, can be baffled in this way.

Similar baffies can be applied to almost any type water tube boiler.

What I claim as new is:

1. In a boiler, a combustion space and a horizontal fiow convection zone having sidewalls, a bridge wall dividing the lower part of the convection zone from the combustion space, a bank of vertical convection tubes spaced inward from the side walls to provide settling chambers adjacent each side wall, the tubes essentially filling the convection zone except for the spaces between the tubes and the settling chambers, a series of vertical baffies spaced along the tube bank, alternate b-afiles extending from the side walls across the chambers toward the center of the tube bank providing a central opening substantially the full length of the tubes, interover the front of the bank.

2. In a boiler, a combustion space and a horizontal flow convection zone having sidewalls, a

bridge wall dividing the lower part of the convection zone from the combustion space, water cooling tubes along the side walls, a bank of vertical convection tubes spaced inward from the side walls to provide settling chambers adjacent each side wall, the tubes essentially filling the convection zone except for the spaces between the tubes and the settling chamber, a series of vertical baiiles spaced along the tube bank, alternate baflies extending from the side walls across the chambers toward the center of the tube bank providing a central opening substantially the full length of the tubes, intermediate bafiies opposite the central opening extending toward the chambers and providing openings around the sides 01' the baifies through'the chambers, and said vertical convection tubes in the convection'zone having their front tubes of the bank spaced from the bridge 'wall to provide an equalizing chamber distributing gases over the front of the bank.

3. In a boiler, a horizontal upper drum, a combustion space at one end of the drum and a horizontal flow convection zone at the other end of the drum, a bridgewall dividing the lower part of the convection zone from the combustion space, a horizontal lower drum extending through the convection zone to the bridge wall, a bank of vertical tubes between the drums in the convection zone, said bank being spaced from the bridge wall to provide an equalizing chamber distributing gases over the front of the bank and said bank extending solidly down the center of the convection zone, said bank of vertical tubes being spaced inward from the sidewalls to provide settling chambers adjacent each sidewall, and a. series of vertical bafiles in the tube bank successively arranged downstream and extending substantially the full height of the tube bank, and the width of said baflies being substantially less than the width of the tube bank, the first bafiles being adjacent but downstream of the front of the tube bank and extending from the sides of the convection zone toward the center to provide a vertical passageway at the center of the tube bank substantially the full length of the tubes, the second of the series of bafiles being spaced from the sides of the convection zone and opposite the passageway whereby the gases flowing through the passageway are deflected toward opposite sides of the convection zone, and the last of the series of baflies extending from the sides of the convection zone toward the center of the tube bank to provide a vertical passageway short of the end of the tube bank and extending substantially the full length of the tubes.

NILS G. SANDSTROM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

